Assigning UWB anchors for client ranging

ABSTRACT

Presented herein are techniques for assigning Ultra-Wideband (UWB) anchors for client ranging. A location server can estimate a coarse location of a mobile device using a localization technique other than a UWB localization technique. The localization technique can involve multiple wireless access points or other radio devices. The location server can define an area around the coarse location to identify a set of candidate anchors for UWB ranging. The set of candidate anchors can be disposed within the area and include at least a subset of the radio devices. The location server can modify the set of candidate anchors to create a modified set of candidate anchors that includes only UWB-enabled devices. The location server can select a primary anchor from the modified set of candidate anchors and send a command to cause a UWB ranging procedure to be initiated between the primary anchor and the mobile device.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of and claims the benefit of priorityto U.S. patent application Ser. No. 17/098,735, filed Nov. 16, 2020, andissued on Oct. 11, 2022, as U.S. Pat. No. 11,470,571, which applicationclaims priority to U.S. Provisional Patent Application No. 63/069,886,entitled “Infrastructure Grouping of UWB Anchors for Client Ranging,”filed Aug. 25, 2020, the entirety of which applications are incorporatedherein by reference.

TECHNICAL FIELD

The present disclosure relates to network equipment and services.

BACKGROUND

Networking architectures have grown increasingly complex incommunications environments, particularly mobile networkingenvironments. In some instances, it is useful to determine a mobiledevice location within a mobile networking environment. While Instituteof Electrical and Electronics Engineers (IEEE) 802.11 (e.g., Wi-Fi®) orBluetooth® ranging techniques may be utilized in some cases to determinemobile device location, such technologies typically provide limitedlocation accuracy.

Ultra-Wideband (UWB), as defined in IEEE 802.15.4a and 802.15.4z, mayoffer improved ranging accuracy over Bluetooth and Wi-Fi. However, UWBranging techniques are not designed for scale. For example, UWB rangingprocedures generally require all UWB anchors and clients to be on thesame channel, which can cause channel saturation and/or signalcollisions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of a system in which techniques for assigning UWBanchors for client ranging may be implemented, according to an exampleembodiment.

FIG. 2 is a block diagram of an access point configured to participatein the techniques presented herein, according to an example embodiment.

FIG. 3 is a block diagram of a mobile device configured to participatein the techniques presented herein, according to an example embodiment.

FIG. 4 is a block diagram of a UWB anchor device configured toparticipate in the techniques presented herein, according to an exampleembodiment.

FIGS. 5-11 are diagrams depicting operations for assigning UWB anchorsfor client ranging, according to an example embodiment.

FIG. 12 is a diagram depicting how UWB ranging operations may beassigned, according to an example embodiment.

FIG. 13 is a flow chart depicting a method for assigning UWB anchors forclient ranging, according to an example embodiment.

FIG. 14 is a flow chart depicting a method for creating a modified setof candidate anchors for client ranging, according to an exampleembodiment.

FIG. 15 is a flow chart depicting a method for selecting a primary UWBanchor for client ranging, according to an example embodiment.

FIG. 16 is a block diagram of a computing device configured to performfunctions associated with the techniques described herein, according toan example embodiment.

DESCRIPTION OF EXAMPLE EMBODIMENTS

Overview

In one embodiment, a location server can be configured to assign UWBanchors for client ranging. The location server can estimate a coarselocation of a mobile device using a localization technique other than aUWB localization technique. The localization technique can involvemultiple radio devices. The location server can define an area aroundthe coarse location to identify a set of candidate anchors for UWBranging for the mobile device. The set of candidate anchors can bedisposed within the area and include at least a subset of the radiodevices. The location server can modify the set of candidate anchors tocreate a modified set of candidate anchors that includes onlyUWB-enabled devices. The location server can select a primary anchorfrom the modified set of candidate anchors and send a command to cause aUWB ranging procedure to be initiated between the primary anchor and themobile device.

Example Embodiments

Presented herein are techniques for assigning UWB anchors for UWB clientranging. Client ranging can be used, e.g., for detecting and/or trackinga location of a mobile device. Client ranging using a UWB localizationtechnique, i.e., a localization technique involving UWB transmissions,is referred to herein as “UWB ranging.” For example, UWB ranging caninclude time-of-flight (ToF), time-of-arrival (ToA),time-difference-of-arrival (TDoA), received signal strength indicator(RSSI), or other analyses of UWB transmissions. UWB ranging isrelatively precise, providing ranging accuracy within about 10centimeters in line-of-sight (LoS) situations. This level of accuracy isuseful for both client-driven and infrastructure-based applicationswhere, for example, Bluetooth Low Energy (BLE) or Wi-Fi-based rangingmay provide disappointing results.

However, UWB ranging protocols are not designed for scale. For example,in IEEE 802.15.4a and IEEE 802.15.4z, UWB ranging is specified for onemobile device ranging against only one or a few UWB anchors. Yet, incertain environments, there may be many available UWB anchors,especially when the UWB anchors are installed near access points atceiling level and in radio frequency (RF) range of one another.

Moreover, UWB protocols generally require all UWB anchors and mobiledevices to be on the same channel. Determining which UWB anchor isassociated to which mobile device can be important to avoid channelsaturation. This is true both for UWB anchors (which may detecttransmissions from many mobile devices but may suffer from collisionswith mobile devices ranging against neighboring UWB anchors) and formobile devices (which may encounter channel saturation and be preventedfrom engaging in the ranging exchanges they need for accurate location).

In an example embodiment, a location server is configured to identify anoptimal set of UWB anchors against which a mobile device should range.For example, the location server can be configured to assign an initialset of UWB anchors for client ranging when a mobile device first entersa space serviced by the UWB anchors. The location server also may beconfigured to dynamically change the UWB anchor assignment if, and as,the mobile device moves within the space.

The space can include a plurality of radio devices, including, e.g., oneor more access points. Each of the radio devices is configured tocommunicate using any radio access technology, such as Wi-Fi, Bluetooth,Bluetooth Low Energy (BLE), IEEE 802.15.4 (low-rate wireless personalarea networks (LR-WPANs)), etc. Each of the radio devices may or may notinclude UWB communication or functionality. The space also may includeone or more UWB anchor devices, which include UWB functionality.

The location server can cooperate with the radio devices to estimate acoarse location of the mobile device using a localization techniqueother than a UWB localization technique, i.e., using a technique thatdoes not involve UWB transmissions. For example, the location server canestimate the coarse location using lateration (e.g., based on RSSIvalues from the access points) and/or an angle-of-arrival (AoA)technique (e.g., based on TDoA values from the access points). As may beappreciated by a person of ordinary skill in the art, lateration mayenable the coarse location to be estimated within, for example,approximately a five to ten meter accuracy of the actual location of themobile device, while an AoA technique may enable the coarse location tobe estimated within about a one to two meter accuracy of the actuallocation of the mobile device.

The location server can define an area around the coarse location toidentify a set of candidate anchors for UWB ranging for the mobiledevice. For example, the location server can use a convex hull algorithmto define a convex hull spanning all access points or other radiodevices within range of one another within an envelope around the coarselocation. The set of candidate anchors can include, e.g., access pointsor other radio devices involved in the coarse location determination,which are disposed within the defined area. The term “candidate anchor”is used herein to refer to any device, which is considered for potentialuse as a UWB anchor for UWB ranging, even if the device ultimately isnot used as a UWB anchor, e.g., because the device does not qualify as aUWB anchor (because it doesn't have UWB capability) or because it is aUWB anchor but nevertheless is not selected for UWB ranging.

The location server can modify the set of candidate anchors to create amodified set of candidate anchors that includes only UWB-enableddevices. For example, the location server can remove from the set ofcandidate anchors any access points or other radio devices that do nothave UWB functionality. In addition, or in the alternative, the locationserver can add to the set of candidate anchors any UWB anchor deviceswithin the defined area that were not involved in the coarse locationdetermination. For example, the UWB anchor devices may not have beeninvolved in the coarse location determination because they arestandalone UWB anchor devices and not integrated with, or attached to,an access point or other radio device, and/or because they do notinclude a type of communication or functionality that was involved inthe coarse location determination.

The location server can select a primary anchor from the modified set ofcandidate anchors and send a command to instruct the primary anchor toinitiate a UWB ranging procedure with the mobile device. For example,the primary anchor can communicate with the mobile device to complete alocation exchange, while secondary anchors in RF proximity to theprimary anchor can operate as “receive-only anchors,” which passivelyreceive UWB transmissions from the mobile device and from the primaryanchor but do not send communications to the mobile device. Thesecondary anchors can, e.g., report the UWB transmissions, and/orinformation based on the UWB transmissions, to the location server forprocessing.

Turning now to FIG. 1 , an example system 100 for assigning UWB anchorsfor client ranging within a space 101 can include a plurality of radiodevices 105 configured to wirelessly communicate with a plurality ofmobile devices 140 via one or more of a variety of differentcommunication technologies. Each of the radio devices 105 can includeany access point or other radio or network device configured tofacilitate a communication involving one or more mobile devices (such asmobile devices 140). For example, the radio devices 105 can include oneor more access points configured to facilitate communication between oneor more of the mobile devices 140 and a network 150. Access points aresometimes referred to herein as “APs” or “WLAN access points.”

Each of the radio devices 105 can communicate with (i.e., sendtransmissions to, and/or receive transmission from) one or more of themobile devices 140 using a relatively short-range wireless local areacommunication technology, such as (but not limited to) Wi-Fi WLAN, BLE,and/or UWB. For example, radio device 105(1) includesbuilt-in/integrated Wi-Fi functionality for communicating with one ormore of the mobile devices 140 over Wi-Fi WLAN, BLE functionality forcommunicating with one or more of the mobile devices 140 over BLE, andUWB functionality for communicating with one or more of the mobiledevices 140 over UWB. Radio device 105(2) includes built-in/integratedWi-Fi functionality and BLE functionality but not UWB functionality.However, radio device 105(2) is configured to achieve UWB functionalityvia a separate, peripheral UWB anchor device 115 connected to radiodevice 105(2). For example, the UWB anchor device 115 can be embodied ina peripheral device connected to radio device 105(2) via a universalserial bus (USB) dongle, a time-synchronized network (TSN) connection,or another connection technology now known or hereinafter developed.Radio device 105(n) also does not include built-in/integrated UWBfunctionality, and is not connected to any peripheral UWB anchor device.Therefore, radio device 105(n) is not configured to achieve UWBfunctionality.

Each of the mobile devices 140 can include any mobile device or otherobject capable of over-the-air RF communications utilizing wirelesslocal area communication technologies such as (but not limited to) Wi-FiWLAN, BLE, and UWB. Each of the mobile devices 140 also may be capableof over-the-air RF communications utilizing one or more wireless widearea communication technologies such as Third Generation PartnershipProject (3GPP) communication technologies (e.g., Fourth Generation(4G)/Long Term Evolution (LTE), Fifth Generation (5G), etc.). Forexample, each of the mobile devices 140 can include a mobile wirelessphone, computer, tablet, smart glasses, Augmented Reality tool, anelectronic tag (which may, e.g., be coupled to, or associated with, anelectronic or non-electronic object), or another device or object nowknown or hereinafter developed. A mobile device is sometimes referred toherein as a “client” or “station.”

Each of the mobile devices 140 is configured to communicate with one ormore of the radio devices 105. For example, each of the mobile devices140 may include Wi-Fi WLAN functionality for communicating with one ormore of the radio devices 105 over Wi-Fi WLAN, BLE functionality forcommunicating with one or more of the radio devices 105 over BLE, and/orUWB functionality for communicating with one or more of the radiodevices 105 over UWB (either directly or via a peripheral UWB anchordevice 115).

The mobile devices 140 also may be configured to communicate over UWBwith one or more standalone UWB anchor devices 120. A standalone UWBanchor device 120 includes functionality for receiving (and potentiallyalso sending and/or processing) UWB transmissions without beingconnected to, or integrated with, a radio device 105. Each standaloneUWB anchor device 120 also may include other communication capabilities,such as BLE wireless communication capabilities and/or wiredcommunication capabilities, e.g., via a connection to a network (such asnetwork 150) over IEEE 802.11, Ethernet, or another connection mechanismnow known or hereinafter developed.

The terms “UWB anchor” and “anchor” are used interchangeably herein torefer to any device or object configured to detect UWB transmissionsfrom one or more mobile devices (e.g., one or more of the mobile devices140). For example, a UWB anchor can include a standalone UWB anchordevice 120, a peripheral UWB anchor device 115 connected to a radiodevice 105(2), and/or a radio device 105(1) with UWB functionality. Aswould be appreciated by a person of ordinary skill in the art, while aUWB anchor can include a radio device 105, not all UWB anchors includeradio devices 105, and not all radio devices 105 constitute UWB anchors.

It should be appreciated that the number, type, and arrangement of theradio devices 105, mobile devices 140, peripheral anchor devices 115,standalone anchor devices 120, and UWB anchors, and their respectiveconnectivity configurations and capabilities, are illustrative and canvary in alternative example embodiments.

The radio devices 105, peripheral UWB anchor device 115, standalone UWBanchor device 120, and mobile devices 140 are configured to communicatewith a control device 180 via a network 150. The network 150 includesany communications medium for transmitting information between two ormore computing devices. For example, the network 150 can include a localarea network (LAN), wide area network (WAN), virtual private network(VPN), Intranet, Internet, hardwire connections, modem connections,wireless connections, or combinations of one or more these items.

The control device 180 includes one or more computing devices, whichinclude a controller 185 and a location server 190. The controller 185includes hardware and/or software that is configured to manage operationof the radio devices 105. For example, the controller 185 may beconfigured to facilitate certain communications involving one or more ofthe mobile devices 140 through one or more of the radio devices 105. Inone form, the controller 185 and the location server 190 may be separateand physically distinct entities. Alternatively, at least certain of thefeatures and/or functionality of the controller 185 and location server190 may be integrated into a single entity, certain of the featuresand/or functionality described herein in connection with the controller185 may be included in, and/or performed by, the location server 190,and/or certain of the features and/or functionality described herein inconnection with the location server 190 may be included in, and/orperformed by, the controller 185.

The location server 190 includes hardware and/or software that isconfigured to manage location-related transmissions involving the radiodevices 105, peripheral UWB anchor device 115, standalone UWB anchordevice 120, and/or mobile devices 140. For example, the location server190 can be configured to cooperate with the radio devices 105,peripheral UWB anchor device 115, standalone UWB anchor device 120,and/or mobile devices 140 to initiate and complete client rangingprocedures within the space 101, e.g., by assigning and/or instructingone or more of the radio devices 105, peripheral UWB anchor device 115,and/or standalone UWB anchor device 120 to complete client rangingprocedures with respect to one or more of the mobile devices 140. Forexample, the location server 190 can be configured so that, when amobile device 140 enters the space 101, the location server 190 assignsone of the radio devices 105, peripheral UWB anchor device 115, orstandalone UWB anchor device 120 as a primary anchor for engaging in alocation exchange with the mobile device 140 and other(s) of the radiodevices 105, peripheral UWB anchor device 115, and/or standalone UWBanchor device 120 as secondary anchors for passively receivingtransmissions from the mobile device 140 and transmissions from theprimary UWB anchor for location processing.

The space 101 can include any indoor or outdoor area, such as a home,school, campus, office building, conference center, stadium, or othervenue or location or portion thereof. The space 101 may support anydensity of mobile devices 140. The location server 190 can be configuredto assign anchors so that accurate client ranging is enabled for each ofthe mobile devices 140 regardless of density. For example, as set forthin more detail below, for a particular mobile device 140, the locationserver 190 can select an optimal set of anchors for client ranging fromall available radio devices 105, peripheral UWB anchor devices 115,and/or standalone UWB anchor devices 120 in the space 101.

The location server 190 can be configured to coordinate client rangingprocedures involving any of a variety of different localizationtechniques. In an example embodiment, the location server 190 can beconfigured to coordinate client ranging procedures involving one or moreUWB localization techniques, such as ToF, ToA, TDoA, RSSI, or anothertechnique involving analysis of UWB transmissions, and/or one or morenon-UWB localization techniques, such as lateration, AoA, or anothertechnique that does not involve UWB transmissions. For example, thelocation server 190 can estimate a coarse location for a mobile device140 using a non-UWB localization technique, select an optimal set of UWBanchor points for UWB ranging based on the coarse location, and use theselected UWB anchor points to determine more precise locationinformation for the mobile device 140 using one or more UWB localizationtechniques. Thus, the location server may limit UWB ranging to selectedUWB anchor points, potentially reducing a likelihood of channelsaturation and/or signal collisions relative to a configuration in whichUWB ranging involves all available or nearby UWB anchor points.

The location server 190 can include logic for performing one or morelocation computations based on the localization techniques. For example,the location server 190 can process time, distance, angle, signalstrength or other information from one or more of the radio devices 105,peripheral UWB anchor devices 115, standalone UWB anchor devices 120,and/or mobile devices 140 to determine and/or track a location of aparticular one of the mobile devices 140. The location server 190 can beconfigured to return results of that processing to the particular one ofthe mobile devices 140, e.g., through one or more of the radio devices105, or to some other entity seeking that location information, if sodesired. In addition, or in the alternative, the radio devices 105,peripheral anchor devices 115, standalone anchor devices 120, and/ormobile devices 140 can be configured to perform certain locationcomputations and, potentially, to report results from those computationsto the location server 190.

Though illustrated in FIG. 1 as discrete components, and as explainedabove, it should be appreciated that the controller 185 and locationserver 190 may be integrated or otherwise reconfigured in any number ofdifferent components without departing from the spirit and scope of thepresent disclosure.

FIG. 2 is a block diagram of an access point 200, according to anexample embodiment. The access point 200 includes a Wi-Fi chipset 220for providing Wi-Fi functionality, a BLE chipset 235 for providing BLEfunctionality, and a UWB chipset 250 for providing UWB functionality.The Wi-Fi chipset 220 includes one or more Wi-Fi radio transceivers 225configured to perform Wi-Fi RF transmission and reception, and one orWi-Fi baseband processors 230 configured to perform Media Access Control(MAC) and physical layer (PHY) modulation/demodulation processing. TheBLE chipset 235 includes a BLE radio transceiver 240 configured toperform BLE RF transmission and reception, and a BLE baseband processor245 configured to perform BLE baseband modulation and demodulation. TheUWB chipset 250 includes a UWB radio transceiver 255 configured toperform UWB RF transmission and reception, and a UWB baseband processor260 configured to perform UWB baseband modulation and demodulation. Forexample, the Wi-Fi chipset 220, BLE chipset 235, and UWB chipset 250 maybe implemented in one or more application-specific integrated circuits(ASICs), field-programmable gate arrays (FPGAs) or other digital logicembodied in one or more integrated circuits.

The access point 200 includes one or more processors 205, which mayembody or include one or more microprocessors and/or microcontrollers.In addition, the access point 200 includes a memory 210 that storescontrol logic 215. The processor(s) 205 are configured to executeinstructions of the control logic 215 to execute various controlfunctions for the access point 200.

As would be understood by a person of ordinary skill in the art, thefeatures and functionality of the access point 200 are illustrative andcan vary in alternative example embodiments. For example, the accesspoint 200 may include more, less, or different chipsets in alternativeexample embodiments. In particular, the access point 200 may not includethe Wi-Fi chipset 220 if the access point 200 does not include Wi-Fifunctionality; the access point 200 may not include the BLE chipset 235if the access point 200 does not include BLE functionality; and theaccess point 200 may not include the UWB chipset 250 if the access point200 does not include UWB functionality. In addition, as would berecognized by a person of ordinary skill in the art, the access point200 may include one or more additional components, such as a networkinterface to provide an IEEE 802.11 connection, Ethernet connection, orother connection, which are not depicted in FIG. 2 for purposes ofsimplicity.

FIG. 3 is a block diagram of a mobile device 300, according to anexample embodiment. As would be appreciated by a person of ordinaryskill in the art, the mobile device 300 includes chipsets similar to thechipsets of an access point, though with configurations for client-sideoperations and mobile device/battery-powered use cases. In particular,as with the access point 200 described above in connection with FIG. 2 ,the mobile device 300 includes a Wi-Fi chipset 320 for providing Wi-Fifunctionality, a BLE chipset 335 for providing BLE functionality, and aUWB chipset 350 for providing UWB functionality, with the Wi-Fi chipset320 including one or more Wi-Fi radio transceivers 325 and one or Wi-Fibaseband processors 330, the BLE chipset 335 including a BLE radiotransceiver 340 and a BLE baseband processor 345, and the UWB chipset350 including a UWB radio transceiver 355 and a UWB baseband processor360. The mobile device 300 also includes one or more processors 305(e.g., microprocessor(s) and/or microcontroller(s)) and a memory 310that stores control logic 315.

As would be understood by a person of ordinary skill in the art, thefeatures and functionality of the mobile device 300 are illustrative andcan vary in alternative example embodiments. For example, as with theaccess point 200 depicted in FIG. 2 , the mobile device 300 can includemore, less, or different components in alternative example embodiments.

FIG. 4 is a block diagram of a UWB anchor device 400, according to anexample embodiment. The UWB anchor device 400 can be, for example, astandalone UWB anchor device or a peripheral UWB anchor device.Accordingly, the UWB anchor device 400 may include some, but not all, ofthe features depicted in FIGS. 2 and 3 for example access point 200 andmobile device 300, respectively. In particular, while the UWB anchordevice 400 includes a UWB chipset 450 (with a UWB radio transceiver 455and UWB baseband processor 460), as well as one or more processors 405(e.g., microprocessor(s) and/or microcontroller(s)) and a memory 410that stores control logic 415, the UWB anchor device 400 does notinclude a Wi-Fi chipset or BLE chipset.

However, the UWB anchor device 400 may include these features, and/orother features not depicted in FIG. 4 , in alternative exampleembodiments. For example, the UWB anchor device 400 can includeadditional communication capabilities beyond UWB, such as BLE wirelesscommunication capabilities and/or wired communication capabilities, inalternative example embodiments. In addition, as noted above, the UWBanchor device 400 (or functionality thereof) may be integrated in, orconnected to, a radio device, such as the access point 200, which mayinclude the same or different components than those depicted in the UWBanchor device 400 of FIG. 4 .

Turning now to FIGS. 5-10 , an example operational flow for assigningUWB anchors for client ranging is now described. Referring first to FIG.5 , in a first stage 500, a mobile device 550 has entered a venue 505.The venue 505 includes any indoor or outdoor area, such as a home,school, campus, office building, conference center, stadium, or othervenue or location or portion thereof. The venue 505 includes a pluralityof access points 510-524 and a plurality of standalone UWB anchordevices 540 and 541. Certain of the access points 510-524, namely accesspoints 510, 511, 512, 513, 514, 515, 516, 517, 518, 519 and 520 (the“APs w/ UWB”), have UWB functionality, while certain other of the accesspoints 510-524, namely access points 521, 522, 523 and 524 (the “APs w/oUWB”), do not have UWB functionality. As described above, each of theAPs w/ UWB 510-520 can achieve UWB functionality either by includingbuilt-in/integrated UWB functionality or by being connected to aperipheral UWB anchor device or other device with UWB functionality. Forsimplicity, the UWB functionality for each of the APs w/ UWB 510-520 isdescribed below with reference to the APs w/ UWB 510-520, though it isto be understood that such functionality may be provided by, or involve,a peripheral UWB device or other device connected to the APs 510-520.

A location server 590 is configured to cooperate with the access points510-524, standalone UWB anchor devices 540 and 541, and/or mobile device550 to provide client ranging for the mobile device 550. For example,the location server 590 can be configured to cause client rangingprocedures to be initiated upon entry of the mobile device 550 into thevenue 505, e.g., by assigning one or more of the access points 510-524and/or standalone UWB anchor devices 540 and 541 as a primary anchor forcompleting a location exchange with the mobile device 550 and other ofthe access points 510-524 and/or standalone UWB anchor devices 540 and541 as secondary anchors for passively receiving transmissions from themobile device 550 for location processing. The location server 590 alsomay be configured to dynamically adjust the anchor assignment if, andas, the mobile device 550 moves within the venue 505. Though depicted asbeing disposed within the venue 505, it should be understood that thelocation server 590 may be located remote from the venue 505, e.g., in acloud-based solution, in alternative example embodiments.

Next, in FIG. 6 , in an example embodiment, the location server 590initiates the client ranging procedure in stage 500 by cooperating withaccess points 510-517 and 522 to estimate a coarse location 605 of themobile device 550 using a localization technique other than a UWBtechnique, i.e., using a technique that does not involve UWBtransmissions. For example, the location server 590 can estimate thecoarse location 605 using lateration (e.g., based on RSSI values fromthe access points 510-517 and 522) and/or an AoA technique. Thelocalization technique may involve, e.g., Wi-Fi, BLE, or other non-UWBtransmissions from/to the access points 510-517 and 522. It should beunderstood that the localization technique, and the number, type, andarrangement of devices involved in the localization technique, may varyin alternative example embodiments. For example, though not involved inthe localization technique depicted in FIG. 6 , one or more UWB anchordevices, such as UWB anchor device 540 and/or UWB anchor device 541, maybe involved in the localization technique in alternative exampleembodiments if, and to the extent that, the UWB anchor devices includeWi-Fi, BLE, or other (non-UWB) functionality that corresponds to atransmission method involved in the localization technique.

As may be appreciated by a person of ordinary skill in the art,lateration may enable the coarse location 605 to be estimated withinabout a five to ten meter accuracy of the actual location of the mobiledevice 550, while an AoA technique may enable the coarse location 605 tobe estimated within about a one to two meter accuracy of the actuallocation of the mobile device 550. Thus, in the first stage 500, thelocation server 590 may determine a general (but not precise) area wherethe mobile device 550 is located, within an accuracy of about 1 meter toabout 7 meters, but perhaps as much as 10 meters.

As shown in FIG. 7 , in a second stage 700, the location server 590defines an area 705 around the coarse location 605 to identify a set ofcandidate anchors for UWB ranging for the mobile device 550. Thecandidate anchors include all of the access points 510-517 and 522(and/or other devices) within the area 705, which were involved in thedetermination of the coarse location 605. For example, the locationserver 590 may use a convex hull algorithm, such as a Slow Convex Hullor Graham's Scan, to define the area 705 as a convex hull spanning allaccess points 510-517 and 522 within RF range of one another within anenvelope around the coarse location 605. In an example embodiment, thedefined area 705 is a closed polygon, with a plurality of line segmentsconnecting each pair of its points (e.g., at one or more of the accesspoints (510 and 512-517) and/or other devices), surrounding the coarselocation 605. A size of the area 705 can vary, but in an exampleembodiment, the area 705 is defined large enough to include at least onecandidate anchor in each of four quadrants (viewed as a “clock”) aroundthe coarse location 605. It should be appreciated that the size andshape of the area 705, and the number, type, and configuration of thecandidate anchors and any other devices therein, are illustrative andshould not be construed as being limiting in any way.

Turning now to FIG. 8 , in a third stage 800, the location server 590determines UWB capabilities (or a lack of UWB capability) for each ofthe candidate anchors. For example, the location server 590, or acontroller or other device in communication with the location server590, can send one or more communications to the candidate anchors todetermine which of the candidate anchors has UWB functionality (whetherintegrated within the candidate anchor or provided through a peripheralor other device). The location server 590 modifies the set of candidateanchors to create a modified set of candidate anchors that includes onlyUWB-enabled devices. In particular, the location server 590 removes fromthe set of candidate anchors any access points, such as access point522, which do not have UWB functionality. The location server 590 alsocan add to the set of candidate anchors any devices, such as standaloneanchor devices 540 and 541, which are located within the area 705 andhave UWB functionality but were not involved in the coarse locationdetermination. For example, these devices may include standalone UWBdevices that do not include a type of functionality that was involved inthe coarse location determination or otherwise were not included in thecoarse location determination.

Next, the location server 590 selects a best possible UWB anchor in themodified set of candidate anchors to be the primary/active anchor for alocation exchange with the mobile device 550. The location server 590also selects secondary anchors for passively receiving transmissionsfrom the mobile device 550 and the primary anchor for locationprocessing. For example, the secondary anchors can act as “observers,”observing and reporting on the client ranging exchange with the primaryanchor. This information can be used, e.g., to compute an accuratelocation for the mobile device 550. For example, time of receptionmeasurements made at the secondary anchors can be used, either alone orin combination with information from the primary anchor, to computedistances from the mobile device 550 to the secondary anchors.

The location server 590 can select the primary and secondary anchors,for example, by forming coherent subgroups of the candidate anchors instage 900 as shown in FIG. 9 , selecting a best subgroup from thecoherent subgroups in a stage 1000 shown in FIG. 10 , and selectingprimary and secondary anchors from the selected subgroup in a stage 1100as shown in FIG. 11 . In stage 900, the location server evaluates, foreach candidate anchor in the modified set of candidate anchors, the UWBreachability to each other candidate anchor. As would be appreciated bya person of ordinary skill in the art, a typical Wi-Fi range is largerthan a typical UWB range. Therefore, while certain candidate anchorshaving Wi-Fi capability may be in Wi-Fi range of one another, they maynot be in UWB range of one another.

More specifically, as shown in FIG. 9 , the location server 590 forms aplurality of subgroups 901-905, with each of the subgroups 901-905including a subset of the candidate anchors that are all in UWB range ofone another. Subgroup 901 includes access point 511, access point 512,access point 513, access point 517, and UWB anchor device 540; subgroup902 includes access point 510, access point 511, UWB anchor device 540,UWB anchor device 541, and access point 514; subgroup 903 includesaccess point 514, access point 511, UWB anchor device 540, access point516, UWB anchor device 541, and access point 515; subgroup 904 includesaccess point 514, access point 511, UWB anchor device 540, access point517, access point 516, and UWB anchor device 541; subgroup 905 includesaccess point 511, access point 512, UWB anchor device 540, access point517, access point 516, and UWB anchor device 541. For example, thelocation server 590 can form as many subgroups as possible from themodified set of candidate anchors. It should be appreciated that thenumber, type, and configuration of the subgroups 901-905, and anydevices therein, are illustrative and should not be construed as beinglimiting in any way.

For each of the subgroups 901-905, the location server 590 calculates adistance to a center of the coarse location 605, e.g., by using one ormore location estimation using noisy measurements techniques, such as amean-square technique, 3-sphere technique, and/or direct Kalmantechnique. In an example embodiment, the coarse location 605 can includean area, rather than a point, and the center of the coarse location 605may be computed as a “center” of that area. For example, the locationserver 590 can use a mean-square reduction computation to sort thesubgroups 901-905 by relative distance to the center of the coarselocation 605.

A shorter distance may be helpful, for example, to achieve a maximize RFsignal with minimal collisions, though distance alone is not adetermining factor. For example, there may be walls or other obstaclesbetween a mobile device 550 and an anchor that are relatively close interms of distance, but for which the RF proximity is not sufficient touse that anchor as a primary anchor for UWB ranging. It can bedesirable, for example, to select a primary anchor that maximizes thelikelihood that as many other anchors (secondary anchors) as possiblewithin the modified set of candidate anchors will receive the locationexchange transmissions from both the mobile device 550 and the primaryanchor, and furthermore, so that there is at least one anchor (primaryor secondary) in each quadrant around the mobile device 550 in order tocompute a reliable triangulation location result.

Starting from a particular one of the subgroups 901-905 with thesmallest distance to the center of the coarse location 605, the locationserver 590 can determine whether any of the subgroups 901-905 includesan anchor that is set as a primary anchor for another mobile device. Ifa particular one of the subgroups 901-905 includes an anchor that is setas a primary anchor for another mobile device, the location server 590may select that particular one of the subgroups 901-905 as a bestsubgroup, and the anchor from that particular one of the subgroup901-905 as a best primary anchor, for the mobile device 550. Forexample, selecting as the primary anchor a device that already isserving as a primary anchor for another mobile device may reducecomplexity for managing collisions across the overall space of the venue505, e.g., by preventing a device from serving as both a primary anchorfor one or more mobile devices and a secondary anchor for one or moreother mobile devices.

If none of the subgroups 901-905 include an anchor that is set as aprimary anchor for another mobile device, then the location server 590can select a one of the subgroups 901-905, which is farthest away fromothers of the subgroups 901-905 and, within that one of the subgroups901-905, can select as the primary anchor an anchor that has a smallestneighbor count. Thus, the location server 590 can minimize a chance ofcollisions between the selected subgroup/anchor and any other group ofanchors formed for UWB ranging with another mobile device. For example,in the example depicted in FIGS. 5-11 , the location server 590 hasselected, in stage 1000 (shown in FIG. 10 ), subgroup 904 as a bestsubgroup for the mobile device 550 and access point 516 within thatsubgroup 905 as the best primary anchor for the mobile device 550.

The location server 590 may select one or more other devices within thesubgroup 904, e.g., access point 514, access point 511, UWB anchordevice 540, access point 517, and/or UWB anchor device 541, as secondary(receive-only) anchors for UWB ranging for the mobile device 550. Forexample, location server 590 may select only a closest x number ofanchors to include as secondary anchors, e.g., to limit the group ofprimary and secondary anchors below a total of six or another maximumnumber of anchors. In addition, or in the alternative, the locationserver 590 may select as secondary anchors any anchors disposed along aperimeter of the area 705 (shown in FIG. 7 ). It should be understoodthat certain of the selected anchors may participate in client ranging,e.g., by receiving ranging exchanges, both for the mobile device 550 andfor one or more other mobile devices. As described in more detail below,with reference to FIG. 12 , the location server 590 can be configured tomaintain a convex hull or other configuration for the anchors whileminimizing collisions among the anchors by spreading transmissions asappropriate.

The location server 590 can be configured to send (or cooperate with acontroller or other device, which sends) commands to cause the selectedanchors to complete a UWB ranging procedure with the mobile device 550.For example, the location server 590 can send (or cooperate with acontroller or other device, which sends) a signal to the primary anchorto invoke a mode in which the primary anchor sends to the mobile device550 a “nudge” message that suggests that the mobile device 550 rangewith the primary anchor. In addition, or in the alternative, thelocation server 590 can engage a hybrid mode in which the mobile device550 is sent a unicast message notifying the mobile device 550 about itsprimary anchor. The mobile device 550 can then send a “nudge” messagethat any device can detect, but with a destination address correspondingonly to the primary anchor so that only the primary anchor responds. Inanother embodiment, the mobile device 550 may use a broadcast ormulticast address, with only the primary anchor answering and only thesecondary anchors considering the message.

Returning to the example depicted in FIGS. 5-11 , the location server590 has selected, in stage 1000, access point 516 as a primary anchorfor mobile device 550. The location server 590 causes access point 516(as shown in FIG. 10 ) to complete a location exchange 1005 with themobile device 550. In stage 1100, shown in FIG. 11 , selected secondaryanchors, namely, access point 511, UWB anchor device 540, and accesspoint 517, passively receive the transmission(s) that the mobile device550 sends to the access point 516 (as the primary anchor) and thetransmission that the access point 516 (as the primary anchor) sends tothe mobile device 550, as shown at 1105 a-1105 c for the mobile device550.

In an example embodiment, the location server 590 can be furtherconfigured to evaluate whether a selected primary anchor is in range ofanother primary anchor (for another mobile device). If so, the locationserver 590 can allocate half the UWB slots to each of the primaryanchors. Then, the selected primary anchor can send a unicast (ormulticast if multiple mobile devices are in the zone) Time-DivisionMultiple Access (TDMA) trigger to the mobile device 550, allocatingtransmission slots to the mobile device 550.

An example mechanism 1200 for allocating UWB slots to primary anchors isshown in FIG. 12 . A first UWB slot 1205 a is assigned to a first mobiledevice for UWB ranging, and a second UWB slot 1205 b is assigned to asecond mobile device for UWB ranging. The first UWB slot 1205 a and thesecond UWB slot 1205 b are separated by a guard interval 1210. Each ofthe UWB slots 1205 a and 1205 b includes at least one burst 1220. Eachburst 1220 includes one or more burst positions 1230. Within each burstposition 1230, there are different chip positions 1240.

A UWB signal sent during a burst position 1230 generally includes ashort-lived pulse. Each pulse includes a relatively wide bandwidthsignal (e.g., 499.2 MHz) that is relatively flat (e.g., with low power).Because the pulse is so short-lived and may not display consistentspectral intensity across the entire bandwidth, it may appear narrow inthe frequency domain and in the time domain. Thus, two different mobiledevices could be assigned the same burst position 1230, and their pulsesmay be: 1) displaying peak intensity on different subsets of the signaland, thus, detectable from each other, or 2) slightly misaligned in timeand, thus, able to coexist without colliding. Accordingly, the locationserver can spread devices into different slots, at a narrower timeresolution level, and the location server can assign devices todifferent burst positions in the same slot. For example, even if twodevices are assigned the same burst position 1230, they may be assigneddifferent chip positions 1240 and, therefore, avoid collisions.

Turning now to FIG. 13 , an example method 1300 is shown for assigningUWB anchors for client ranging, according to an example embodiment. Instep 1305, a location server estimates a coarse location of a mobiledevice using a non-UWB localization technique, i.e., using a techniquethat does not involve UWB transmissions. For example, the locationserver can estimate the coarse location using lateration and/or an AoAtechnique. The localization technique may involve, e.g., Wi-Fi, BLE, orother non-UWB transmissions from/to one or more access points or otherradio devices.

In step 1310, the location server defines an area around the coarselocation to identify a set of candidate anchors for UWB ranging for themobile device. For example, the location server can use a convex hullalgorithm, such as a Slow Convex Hull or Graham's Scan, to define thearea as a convex hull spanning all access points within RF range of oneanother within an envelope around the coarse location. The candidateanchors can include, e.g., at least a subset of the devices involved indetermining the coarse location in step 1305.

In step 1315, the location server modifies the set of candidate anchorsto create a modified set of candidate anchors that includes onlyUWB-enabled devices. For example, the location server can create themodified set of candidate anchors by removing from the set of candidateanchors any access points or other radio devices, which do not have UWBfunctionality, and adding to the set of candidate anchors any deviceswhich are located within the area and have UWB functionality but werenot involved in the coarse location determination. Operations that maybe performed during step 1315 are described in more detail below withreference to FIG. 14 .

In step 1320, the location server selects a primary anchor from themodified set of candidate anchors. For example, the location server canselect the primary anchor by creating a plurality of coherent subgroupsof the candidate anchors that are within a UWB range of one another andthen selecting a primary anchor based on one or more characteristics ofthe subgroups. Operations that may be performed during step 1320 aredescribed in more detail below with reference to FIG. 15 .

In step 1325, the location server selects secondary anchors within UWBrange of the primary anchor. For example, the location server can selectone or more (or all) secondary anchors from the subgroup correspondingto the selected primary anchor. The location server may, for example,select a number of secondary anchors so that a total number of anchorsparticipating in UWB ranging with the mobile device is below apredetermined maximum (e.g., six or less total anchors). For example,the location server can select only a closest x number of anchors to themobile device to include as secondary anchors. In addition, or in thealternative, the location server may select as secondary anchors anyanchors disposed along a perimeter of the area defined in step 1310.

In step 1330, the location server causes a command to be sent (either bythe location server or a controller or other device cooperating with thelocation server) to cause the selected anchors to complete a UWB rangingprocedure with the mobile device. The primary anchor can communicatewith the mobile device to complete a location exchange, while thesecondary anchors around can operate as “receive-only anchors,” whichpassively receive UWB transmissions from the mobile device and theprimary anchor but do not send communications to the mobile device. Thesecondary anchors may, for example, report the UWB transmissions, and/orinformation (times of arrival, etc.) based on the received UWBtransmissions, to the location server for processing.

For example, the location server can send (or cooperate with acontroller or other device, which sends) a signal to the primary anchorto invoke a mode in which the primary anchor sends to the mobile devicea “nudge” message that suggests that the mobile device range with theprimary anchor. In addition, or in the alternative, the location servercan engage a hybrid mode in which the mobile device is sent a unicastmessage notifying the mobile device about its primary anchor. The mobiledevice can then send a “nudge” message that any device can detect, butwith a destination address corresponding only to the primary anchor sothat only the primary anchor responds. In another embodiment, the mobiledevice may use a broadcast or multicast address, with only the primaryanchor answering back to the mobile device, and the secondary anchorsnot responding to the message.

FIG. 14 is a flow chart depicting in more detail operations that may beperformed at step 1315 for creating a modified set of candidate anchorsfor client ranging, according to an example embodiment. The operationsof step 1315 continue from step 1310 of the method 1300 described above.In step 1405, the location server removes from the set of candidateanchors at least one access point or other radio device that is not UWBenabled. For example, the radio device may include Wi-Fi, BLE, oranother communication technology, but not UWB functionality. That othercommunication technology may have been used, e.g., in the estimation ofthe coarse location in step 1305 of the method 1300.

In step 1410, the location server adds to the set of candidate anchorsat least one UWB-enabled device that was not involved in the estimationof the coarse location in step 1305. For example, the UWB anchor devicesmay not have been involved in the coarse location determination becausethey are standalone UWB anchor devices and not integrated with, orattached to, an access point or other radio device, and/or because theydo not include a type of functionality that was involved in the coarselocation determination. Each of the one or more UWB-enabled devices thatare added to the set of candidate anchors may, for example, be disposedwithin the area that was defined in step 1310. Processing continues tostep 1320 in FIG. 13 .

FIG. 15 is a flow chart depicting operations that may be performed instep 1320 for selecting a primary UWB anchor for client ranging,according to an example embodiment. The operations of step 1320 continuefrom step 1315 of the method 1300 described above. In step 1505, thelocation server identifies a plurality of subgroups from the modifiedset of candidate anchors (that was created in step 1315). Each of thesubgroups includes anchors from the modified set of candidate anchors.For example, the location server can identify subgroups that eachinclude a subset of the candidate anchors that are all in UWB range ofone another.

In step 1510, the location server calculates, for each of the subgroups,a distance to the coarse location. For example, the location server cancalculate a distance to a center of the coarse location using one ormore location estimation using noisy measurements techniques, such as amean-square technique, 3-sphere technique, and/or direct Kalmantechnique. In step 1515, the location server determines, e.g., in anorder based on the calculating, whether any of the subgroups includes ananchor that is set as a primary anchor for another mobile device. Forexample, the location server can use a mean-square reduction computationto sort the subgroups by relative distance to the center of the coarselocation and then determine, in order of shortest to longest, whethereach of the subgroups includes an anchor that is set as a primary anchorfor another mobile device.

If, at 1520, the location server determines that one of the subgroupsincludes an anchor that is set as a primary anchor for another mobiledevice, then the process continues to step 1525. In step 1525, thelocation server selects the anchor that is set as the primary anchor forthe other mobile device as the primary anchor. If the location serverdetermines in step 1515 that none of the subgroups includes an anchorthat is set as a primary anchor for another mobile device, thenprocessing continues to step 1530 where the location server identifies aparticular one of the subgroups that is farthest away from others of thesubgroups. In step 1535, the location server selects as the primaryanchor an anchor in the one of the subgroups, which has a smallestneighbor count. Thus, the location server can minimize a chance ofcollisions between the selected subgroup/anchor and any other group ofanchors formed for UWB ranging with another mobile device. Processingthen continues to step 1325 shown in FIG. 13 .

As would be recognized by a person of skill in the art, the stepsassociated with the methods of the present disclosure, including method1300, the operations of step 1315, and the operations of step 1320, mayvary widely. Steps may be added, removed, altered, combined, andreordered without departing from the spirit or the scope of the presentdisclosure. Therefore, the example methods are to be consideredillustrative and not restrictive, and the examples are not to be limitedto the details given herein but may be modified within the scope of theappended claims.

Referring to FIG. 16 , FIG. 16 illustrates a hardware block diagram of acomputing device 1600 that may perform functions associated withoperations discussed herein in connection with the techniques depictedin FIGS. 1-15 . In various embodiments, a computing device, such ascomputing device 1600 or any combination of computing devices 1600, maybe configured as any entity/entities as discussed for the techniquesdepicted in connection with FIG. 16 , such as controller 185 or locationserver 190 shown in FIG. 1 or location server 590 shown in FIGS. 5-11 ,in order to perform operations of the various techniques discussedherein.

In at least one embodiment, the computing device 1600 may include one ormore processor(s) 1605, one or more memory element(s) 1610, storage1615, a bus 1620, one or more network processor unit(s) 1625interconnected with one or more network input/output (I/O) interface(s)1630, one or more I/O interface(s) 1635, and control logic 1640. Invarious embodiments, instructions associated with logic for computingdevice 1600 can overlap in any manner and are not limited to thespecific allocation of instructions and/or operations described herein.

In at least one embodiment, processor(s) 1605 is/are at least onehardware processor configured to execute various tasks, operationsand/or functions for computing device 1600 as described herein accordingto software and/or instructions configured for computing device 1600.Processor(s) 1605 (e.g., a hardware processor) can execute any type ofinstructions associated with data to achieve the operations detailedherein. In one example, processor(s) 1605 can transform an element or anarticle (e.g., data, information) from one state or thing to anotherstate or thing. Any of potential processing elements, microprocessors,digital signal processor, baseband signal processor, modem, PHY,controllers, systems, managers, logic, and/or machines described hereincan be construed as being encompassed within the broad term ‘processor’.

In at least one embodiment, memory element(s) 1610 and/or storage 1615is/are configured to store data, information, software, and/orinstructions associated with computing device 1600, and/or logicconfigured for memory element(s) 1610 and/or storage 1615. For example,any logic described herein (e.g., control logic 1640) can, in variousembodiments, be stored for computing device 1600 using any combinationof memory element(s) 1610 and/or storage 1615. Note that in someembodiments, storage 1615 can be consolidated with memory element(s)1610 (or vice versa), or can overlap/exist in any other suitable manner.

In at least one embodiment, bus 1620 can be configured as an interfacethat enables one or more elements of computing device 1600 tocommunicate in order to exchange information and/or data. Bus 1620 canbe implemented with any architecture designed for passing control, dataand/or information between processors, memory elements/storage,peripheral devices, and/or any other hardware and/or software componentsthat may be configured for computing device 1600. In at least oneembodiment, bus 1620 may be implemented as a fast kernel-hostedinterconnect, potentially using shared memory between processes (e.g.,logic), which can enable efficient communication paths between theprocesses.

In various embodiments, network processor unit(s) 1625 may enablecommunication between computing device 1600 and other systems, entities,etc., via network I/O interface(s) 1630 to facilitate operationsdiscussed for various embodiments described herein. In variousembodiments, network processor unit(s) 1625 can be configured as acombination of hardware and/or software, such as one or more Ethernetdriver(s) and/or controller(s) or interface cards, Fibre Channel (e.g.,optical) driver(s) and/or controller(s), and/or other similar networkinterface driver(s) and/or controller(s) now known or hereafterdeveloped to enable communications between computing device 1600 andother systems, entities, etc. to facilitate operations for variousembodiments described herein. In various embodiments, network I/Ointerface(s) 1630 can be configured as one or more Ethernet port(s),Fibre Channel ports, and/or any other I/O port(s) now known or hereafterdeveloped. Thus, the network processor unit(s) 1625 and/or network I/Ointerface(s) 1630 may include suitable interfaces for receiving,transmitting, and/or otherwise communicating data and/or information ina network environment.

I/O interface(s) 1635 allow for input and output of data and/orinformation with other entities that may be connected to computer device1600. For example, I/O interface(s) 1635 may provide a connection toexternal devices such as a keyboard, keypad, a touch screen, and/or anyother suitable input and/or output device now known or hereafterdeveloped. In some instances, external devices can also include portablecomputer readable (non-transitory) storage media such as databasesystems, thumb drives, portable optical or magnetic disks, and memorycards. In still some instances, external devices can be a mechanism todisplay data to a user, such as, for example, a computer monitor, adisplay screen, or the like.

In various embodiments, control logic 1640 can include instructionsthat, when executed, cause processor(s) 1605 to perform operations,which can include, but not be limited to, providing overall controloperations of computing device; interacting with other entities,systems, etc. described herein; maintaining and/or interacting withstored data, information, parameters, etc. (e.g., memory element(s),storage, data structures, databases, tables, etc.); combinationsthereof; and/or the like to facilitate various operations forembodiments described herein.

The programs described herein (e.g., control logic 1640) may beidentified based upon application(s) for which they are implemented in aspecific embodiment. However, it should be appreciated that anyparticular program nomenclature herein is used merely for convenience;thus, embodiments herein should not be limited to use(s) solelydescribed in any specific application(s) identified and/or implied bysuch nomenclature.

In various embodiments, entities as described herein may storedata/information in any suitable volatile and/or non-volatile memoryitem (e.g., magnetic hard disk drive, solid state hard drive,semiconductor storage device, random access memory (RAM), read onlymemory (ROM), erasable programmable read only memory (EPROM), ASIC,etc.), software, logic (fixed logic, hardware logic, programmable logic,analog logic, digital logic), hardware, and/or in any other suitablecomponent, device, element, and/or object as may be appropriate. Any ofthe memory items discussed herein should be construed as beingencompassed within the broad term ‘memory element’. Data/informationbeing tracked and/or sent to one or more entities as discussed hereincould be provided in any database, table, register, list, cache,storage, and/or storage structure: all of which can be referenced at anysuitable timeframe. Any such storage options may also be included withinthe broad term ‘memory element’ as used herein.

Note that in certain example implementations, operations as set forthherein may be implemented by logic encoded in one or more tangible mediathat is capable of storing instructions and/or digital information andmay be inclusive of non-transitory tangible media and/or non-transitorycomputer readable storage media (e.g., embedded logic provided in: anASIC, digital signal processing (DSP) instructions, software[potentially inclusive of object code and source code], etc.) forexecution by one or more processor(s), and/or other similar machine,etc. Generally, memory element(s) 1610 and/or storage 1615 can storedata, software, code, instructions (e.g., processor instructions),logic, parameters, combinations thereof, and/or the like used foroperations described herein. This includes memory element(s) 1610 and/orstorage 1615 being able to store data, software, code, instructions(e.g., processor instructions), logic, parameters, combinations thereof,or the like that are executed to carry out operations in accordance withteachings of the present disclosure.

In some instances, software of the present embodiments may be availablevia a non-transitory computer useable medium (e.g., magnetic or opticalmediums, magneto-optic mediums, CD-ROM, DVD, memory devices, etc.) of astationary or portable program product apparatus, downloadable file(s),file wrapper(s), object(s), package(s), container(s), and/or the like.In some instances, non-transitory computer readable storage media mayalso be removable. For example, a removable hard drive may be used formemory/storage in some implementations. Other examples may includeoptical and magnetic disks, thumb drives, and smart cards that can beinserted and/or otherwise connected to a computing device for transferonto another computer readable storage medium.

In summary, in one form, a computer-implemented method can includeestimating, by a location server, a coarse location of a mobile deviceusing a localization technique other than a UWB localization technique.For example, the estimating may be performed in response to the mobiledevice entering a venue where the area is located. The localizationtechnique can involve, e.g., a plurality of radio devices. The locationserver can define an area around the coarse location to identify a setof candidate anchors for UWB ranging for the mobile device. For example,the location server can define the area around the coarse location usinga convex hull algorithm.

The set of candidate anchors can, e.g., be disposed within the area andcomprise at least a subset of the plurality of radio devices. Thelocation server can modify the set of candidate anchors to create amodified set of candidate anchors that includes only UWB-enableddevices. For example, the location server can create the modified set ofcandidate anchors by removing from the set of candidate anchors at leastone radio device within the subset of the plurality of radio devicesthat is not UWB-enabled. In addition, or in the alternative, thelocation server can add to the set of candidate anchors at least oneUWB-enabled device that was not involved in the estimating.

The location server can select a primary anchor from the modified set ofcandidate anchors. For example, selecting can include identifying aplurality of subgroups from the modified set of candidate anchors, eachof the plurality of subgroups comprising a plurality of anchors from themodified set of candidate anchors, which are within a UWB range of oneanother; and selecting the primary anchor from a particular one of theplurality of subgroups based on a characteristic of the particular oneof the plurality of subgroups. Selecting the primary anchor from theparticular one of the plurality of subgroups can include, e.g.,determining whether any of the plurality of subgroups includes an anchorthat is set as a primary anchor for another mobile device; and inresponse to determining that one of the plurality of subgroups includesa particular anchor that is set as a primary anchor for another mobiledevice, selecting the particular anchor as the primary anchor.

For example, the location server can calculate, for each of theplurality of subgroups, a distance to a center of the coarse locationand complete the determining (re: whether any of the plurality ofsubgroups includes an anchor that is set as a primary anchor for anothermobile device) in an order based on the calculating. In response todetermining that none of the plurality of subgroups includes an anchorthat is set as a primary anchor for another mobile device, the locationserver can, e.g., identify a one of the plurality of subgroups that isfarthest away from others of the plurality of subgroups; and select asthe primary anchor an anchor in the one of the plurality of subgroups,which anchor has a smallest neighbor count. A command can be sent fromthe location server to the primary anchor to instruct the primary anchorto initiate a UWB ranging procedure with the mobile device.

In another form, an apparatus can include an interface configured toenable network communications, and one or more processors coupled to theinterface. The one or more processors can be configured to performoperations including: estimating a coarse location of a mobile deviceusing a localization technique other than an ultra-wide band (UWB)localization technique, the localization technique involving a pluralityof radio devices; defining an area around the coarse location toidentify a set of candidate anchors for UWB ranging for the mobiledevice, the set of candidate anchors being disposed within the area andcomprising at least a subset of the plurality of radio devices;modifying the set of candidate anchors to create a modified set ofcandidate anchors that includes only UWB-enabled devices; selecting aprimary anchor from the modified set of candidate anchors; and sending acommand to cause a UWB ranging procedure to be initiated between theprimary anchor and the mobile device.

In another form, one or more non-transitory computer readable storagemedia can include instructions that, when executed by at least oneprocessor, are operable to: estimate a coarse location of a mobiledevice using a localization technique other than an ultra-wide band(UWB) localization technique, the localization technique involving aplurality of radio devices; define an area around the coarse location toidentify a set of candidate anchors for UWB ranging for the mobiledevice, the set of candidate anchors being disposed within the area andcomprising at least a subset of the plurality of radio devices; modifythe set of candidate anchors to create a modified set of candidateanchors that includes only UWB-enabled devices; select a primary anchorfrom the modified set of candidate anchors; and send a command to causea UWB ranging procedure to be initiated between the primary anchor andthe mobile device.

Variations and Implementations

Embodiments described herein may include one or more networks, which canrepresent a series of points and/or network elements of interconnectedcommunication paths for receiving and/or transmitting messages (e.g.,packets of information) that propagate through the one or more networks.These network elements offer communicative interfaces that facilitatecommunications between the network elements. A network can include anynumber of hardware and/or software elements coupled to (and incommunication with) each other through a communication medium. Suchnetworks can include, but are not limited to, any local area network(LAN), virtual LAN (VLAN), wide area network (WAN) (e.g., the Internet),software defined WAN (SD-WAN), wireless local area (WLA) access network,wireless wide area (WWA) access network, metropolitan area network(MAN), Intranet, Extranet, virtual private network (VPN), Low PowerNetwork (LPN), Low Power Wide Area Network (LPWAN), Machine to Machine(M2M) network, Internet of Things (IoT) network, Ethernetnetwork/switching system, any other appropriate architecture and/orsystem that facilitates communications in a network environment, and/orany suitable combination thereof.

Networks through which communications propagate can use any suitabletechnologies for communications including wireless communications (e.g.,4G/5G/nG, IEEE 802.11 (e.g., Wi-Fi/Wi-Fi6®), IEEE 802.16 (e.g.,Worldwide Interoperability for Microwave Access (WiMAX)),Radio-Frequency Identification (RFID), Near Field Communication (NFC),Bluetooth™, mm.wave, Ultra-Wideband (UWB), etc.), and/or wiredcommunications (e.g., T1 lines, T3 lines, digital subscriber lines(DSL), Ethernet, Fibre Channel, etc.). Generally, any suitable means ofcommunications may be used such as electric, sound, light, infrared,and/or radio to facilitate communications through one or more networksin accordance with embodiments herein. Communications, interactions,operations, etc. as discussed for various embodiments described hereinmay be performed among entities that may directly or indirectlyconnected utilizing any algorithms, communication protocols, interfaces,etc. (proprietary and/or non-proprietary) that allow for the exchange ofdata and/or information.

In various example implementations, entities for various embodimentsdescribed herein can encompass network elements (which can includevirtualized network elements, functions, etc.) such as, for example,network appliances, forwarders, routers, servers, switches, gateways,bridges, loadbalancers, firewalls, processors, modules, radioreceivers/transmitters, or any other suitable device, component,element, or object operable to exchange information that facilitates orotherwise helps to facilitate various operations in a networkenvironment as described for various embodiments herein. Note that withthe examples provided herein, interaction may be described in terms ofone, two, three, or four entities. However, this has been done forpurposes of clarity, simplicity and example only. The examples providedshould not limit the scope or inhibit the broad teachings of systems,networks, etc. described herein as potentially applied to a myriad ofother architectures.

Communications in a network environment can be referred to herein as‘messages’, ‘messaging’, ‘signaling’, ‘data’, ‘content’, ‘objects’,‘requests’, ‘queries’, ‘responses’, ‘replies’, etc. which may beinclusive of packets. As referred to herein and in the claims, the term‘packet’ may be used in a generic sense to include packets, frames,segments, datagrams, and/or any other generic units that may be used totransmit communications in a network environment. Generally, a packet isa formatted unit of data that can contain control or routing information(e.g., source and destination address, source and destination port,etc.) and data, which is also sometimes referred to as a ‘payload’,‘data payload’, and variations thereof. In some embodiments, control orrouting information, management information, or the like can be includedin packet fields, such as within header(s) and/or trailer(s) of packets.Internet Protocol (IP) addresses discussed herein and in the claims caninclude any IP version 4 (IPv4) and/or IP version 6 (IPv6) addresses.

To the extent that embodiments presented herein relate to the storage ofdata, the embodiments may employ any number of any conventional or otherdatabases, data stores or storage structures (e.g., files, databases,data structures, data or other repositories, etc.) to store information.

Note that in this Specification, references to various features (e.g.,elements, structures, nodes, modules, components, engines, logic, steps,operations, functions, characteristics, etc.) included in ‘oneembodiment’, ‘example embodiment’, ‘an embodiment’, ‘anotherembodiment’, ‘certain embodiments’, ‘some embodiments’, ‘variousembodiments’, ‘other embodiments’, ‘alternative embodiment’, and thelike are intended to mean that any such features are included in one ormore embodiments of the present disclosure, but may or may notnecessarily be combined in the same embodiments. Note also that amodule, engine, client, controller, function, logic or the like as usedherein in this Specification, can be inclusive of an executable filecomprising instructions that can be understood and processed on aserver, computer, processor, machine, compute node, combinationsthereof, or the like and may further include library modules loadedduring execution, object files, system files, hardware logic, softwarelogic, or any other executable modules.

It is also noted that the operations and steps described with referenceto the preceding figures illustrate only some of the possible scenariosthat may be executed by one or more entities discussed herein. Some ofthese operations may be deleted or removed where appropriate, or thesesteps may be modified or changed considerably without departing from thescope of the presented concepts. In addition, the timing and sequence ofthese operations may be altered considerably and still achieve theresults taught in this disclosure. The preceding operational flows havebeen offered for purposes of example and discussion. Substantialflexibility is provided by the embodiments in that any suitablearrangements, chronologies, configurations, and timing mechanisms may beprovided without departing from the teachings of the discussed concepts.

As used herein, unless expressly stated to the contrary, use of thephrase ‘at least one of’, ‘one or more of’, ‘and/or’, variationsthereof, or the like are open-ended expressions that are bothconjunctive and disjunctive in operation for any and all possiblecombination of the associated listed items. For example, each of theexpressions ‘at least one of X, Y and Z’, ‘at least one of X, Y or Z’,‘one or more of X, Y and Z’, ‘one or more of X, Y or Z’ and ‘X, Y and/orZ’ can mean any of the following: 1) X, but not Y and not Z; 2) Y, butnot X and not Z; 3) Z, but not X and not Y; 4) X and Y, but not Z; 5) Xand Z, but not Y; 6) Y and Z, but not X; or 7) X, Y, and Z.

Additionally, unless expressly stated to the contrary, the terms‘first’, ‘second’, ‘third’, etc., are intended to distinguish theparticular nouns they modify (e.g., element, condition, node, module,activity, operation, etc.). Unless expressly stated to the contrary, theuse of these terms is not intended to indicate any type of order, rank,importance, temporal sequence, or hierarchy of the modified noun. Forexample, ‘first X’ and ‘second X’ are intended to designate two ‘X’elements that are not necessarily limited by any order, rank,importance, temporal sequence, or hierarchy of the two elements. Furtheras referred to herein, ‘at least one of’ and ‘one or more of’ can berepresented using the ‘(s)’ nomenclature (e.g., one or more element(s)).

One or more advantages described herein are not meant to suggest thatany one of the embodiments described herein necessarily provides all ofthe described advantages or that all the embodiments of the presentdisclosure necessarily provide any one of the described advantages.Numerous other changes, substitutions, variations, alterations, and/ormodifications may be ascertained to one skilled in the art and it isintended that the present disclosure encompass all such changes,substitutions, variations, alterations, and/or modifications as fallingwithin the scope of the appended claims.

What is claimed is:
 1. A computer-implemented method comprising:identifying a set of candidate anchors for ultra-wide band (UWB) rangingfor a mobile device, the set of candidate anchors being disposed withinan area around a coarse location of the mobile device; modifying the setof candidate anchors to create a modified set of candidate anchors thatincludes only UWB-enabled devices; selecting a primary anchor from themodified set of candidate anchors; and sending a command to cause a UWBranging procedure to be initiated between the primary anchor and themobile device.
 2. The computer-implemented method of claim 1, furthercomprising: estimating the coarse location of the mobile device using alocalization technique other than a UWB localization technique, thelocalization technique involving a plurality of radio devices includingat least one of radio devices that are UWB-enabled devices or radiodevices that are not UWB-enabled.
 3. The computer-implemented method ofclaim 2, further comprising: defining an area around the coarse locationto identify the set of candidate anchors for UWB ranging for the mobiledevice, the set of candidate anchors being disposed within the area andcomprising at least a subset of the plurality of radio devices.
 4. Thecomputer-implemented method of claim 3, wherein the defining comprisesusing a convex hull algorithm to define the area.
 5. Thecomputer-implemented method of claim 3, wherein the modifying comprisesremoving from the set of candidate anchors at least one radio devicewithin the subset of the plurality of radio devices that is notUWB-enabled.
 6. The computer-implemented method of claim 3, wherein themodifying comprises adding to the set of candidate anchors at least oneUWB-enabled device that was not involved in the estimating.
 7. Thecomputer-implemented method of claim 1, wherein the selecting comprises:identifying a plurality of subgroups from the modified set of candidateanchors that are within a UWB range of one another; and selecting theprimary anchor from a particular one of the plurality of subgroups basedon a characteristic of the particular one of the plurality of subgroups.8. An apparatus comprising: an interface configured to enable networkcommunications; and one or more processors coupled to the interface andconfigured to perform operations comprising: identifying a set ofcandidate anchors for ultra-wide band (UWB) ranging for a mobile device,the set of candidate anchors being disposed within an area around acoarse location of the mobile device; modifying the set of candidateanchors to create a modified set of candidate anchors that includes onlyUWB-enabled devices; selecting a primary anchor from the modified set ofcandidate anchors; and sending a command to cause a UWB rangingprocedure to be initiated between the primary anchor and the mobiledevice.
 9. The apparatus of claim 8, wherein the one or more processorsare further configured to perform operations including: estimating thecoarse location of the mobile device using a localization techniqueother than a UWB localization technique, the localization techniqueinvolving a plurality of radio devices including at least one of radiodevices that are UWB-enabled devices or radio devices that are notUWB-enabled.
 10. The apparatus of claim 9, wherein the one or moreprocessors are further configured to perform operations including:defining an area around the coarse location to identify the set ofcandidate anchors for UWB ranging for the mobile device, the set ofcandidate anchors being disposed within the area and comprising at leasta subset of the plurality of radio devices.
 11. The apparatus of claim10, wherein the defining comprises using a convex hull algorithm todefine the area.
 12. The apparatus of claim 10, wherein the modifyingcomprises removing from the set of candidate anchors at least one radiodevice within the subset of the plurality of radio devices that is notUWB-enabled.
 13. The apparatus of claim 10, wherein the modifyingcomprises adding to the set of candidate anchors at least oneUWB-enabled device that was not involved in the estimating.
 14. Theapparatus of claim 8, wherein the selecting comprises: identifying aplurality of subgroups from the modified set of candidate anchors thatare within a UWB range of one another; and selecting the primary anchorfrom a particular one of the plurality of subgroups based on acharacteristic of the particular one of the plurality of subgroups. 15.One or more non-transitory computer readable storage media comprisinginstructions that, when executed by at least one processor, cause theprocessor to: identify a set of candidate anchors for ultra-wide band(UWB) ranging for a mobile device, the set of candidate anchors beingdisposed within an area around a coarse location of the mobile device;modify the set of candidate anchors to create a modified set ofcandidate anchors that includes only UWB-enabled devices; select aprimary anchor from the modified set of candidate anchors; and send acommand to cause a UWB ranging procedure to be initiated between theprimary anchor and the mobile device.
 16. The one or more non-transitorycomputer readable storage media of claim 15, wherein the instructionsfurther cause the processor to: estimate the coarse location of themobile device using a localization technique other than a UWBlocalization technique, the localization technique involving a pluralityof radio devices including at least one of radio devices that areUWB-enabled devices or radio devices that are not UWB-enabled.
 17. Theone or more non-transitory computer readable storage media of claim 16,wherein the instructions further cause the processor to: define an areaaround the coarse location to identify the set of candidate anchors forUWB ranging for the mobile device, the set of candidate anchors beingdisposed within the area and comprising at least a subset of theplurality of radio devices.
 18. The one or more non-transitory computerreadable storage media of claim 17, wherein the instructions furthercause the processor to: define the area using a convex hull algorithm.19. The one or more non-transitory computer readable storage media ofclaim 17, wherein the instructions further cause the processor to:modify the set of candidate anchors to create the modified set ofcandidate anchors by removing from the set of candidate anchors at leastone radio device within the subset of the plurality of radio devicesthat is not UWB-enabled.
 20. The one or more non-transitory computerreadable storage media of claim 17, wherein the instructions furthercause the processor to: modify the set of candidate anchors to createthe modified set of candidate anchors by adding to the set of candidateanchors at least one UWB-enabled device that was not involved in theestimate.